The association of HLA B*15:02 allele and Stevens–Johnson syndrome/toxic epidermal necrolysis induced by aromatic anticonvulsant drugs in a South Indian population

Abstract

Background

The presence of HLA-B*15:02 allele is considered a risk factor for development of Stevens–Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) in patients taking aromatic anticonvulsant drugs like carbamazepine and phenytoin. The genetic association is ethnicity specific. Testing for HLA-B*15:02 allele is suggested as a prerequisite before starting carbamazepine in certain ethnic groups. There are only a few/no studies from south India on HLA association of SJS/TEN.

Aims

To identify any association between HLA-B*15:02 allele and SJS/TEN induced by carbamazepine/phenytoin among native population.

Methods (including settings, design, and statistical analysis used)

A case–control study done in a tertiary care center at Kottayam in Kerala state of south India. Cases were 12 native patients who developed SJS/TEN owing to aromatic anticonvulsant drugs (phenytoin – 8; carbamazepine – 4), and controls were 11 persons tolerant to these drugs from unrelated families of the same ethnic group. HLA-B typing was done by PCR SSP method.

Results

There was only one HLA-B*15:02 carrier among cases and controls. He/she had SJS/TEN induced by carbamazepine.

Conclusions

Association of HLA-B*15:02 with phenytoin-induced SJS/TEN is rare in the population studied. The one limitation of the study was the small sample size.